401k Calculator & Guide
Compare hypothetical Roth and traditional 401(k) outcomes using your contribution, investment return and estimated tax rates.
Tax treatment generally occurs when money is distributed.
Contributions are taxed before entering the account; qualified distributions are generally tax-free.
Enter your assumptions to estimate the future value of an equal employee contribution and the estimated after-tax value of each account.
The central difference is generally when income tax is applied to the employee contribution and its investment growth.
Traditional employee elective deferrals generally aren't included in taxable income when contributed. Distributions are generally taxable when withdrawn.
Designated Roth contributions are included in income when made. Qualified distributions from the Roth account are generally not included in taxable income.
The accounts can use the same workplace plan while applying different tax treatment to employee contributions and distributions.
| Feature | Traditional 401(k) | Roth 401(k) |
|---|---|---|
| Employee contribution | Generally pre-tax | After-tax |
| Tax treatment at contribution | Generally reduces current taxable income | Included in current taxable income |
| Investment growth | Tax-deferred | Generally tax-free when distributed as part of a qualified distribution |
| Qualified retirement distribution | Generally taxable | Generally tax-free |
| Income limit for participation | No general income limit for making a designated contribution | No income limit for designated Roth 401(k) contributions |
| Employee contribution limit | Shares the applicable 401(k) elective-deferral limit | Shares the applicable 401(k) elective-deferral limit |
| Employer match | May be available | May be available if the plan permits |
| Tax timing | Generally later | Generally now |
The calculator intentionally uses assumptions instead of treating one account type as universally preferable.
A traditional contribution can affect taxable income today, while a designated Roth contribution is included in current taxable income.
The calculator applies your estimated retirement tax rate to the traditional balance to illustrate the effect of future taxation.
The longer the money remains invested, the more the assumed return affects the modeled account values.
Higher contributions generally increase the amount available for investment in either account type.
Your plan's matching formula can materially affect total retirement contributions.
Years until retirement affect how long contributions and investment growth are modeled.
Roth and traditional employee deferrals share the applicable employee elective-deferral limit.
Traditional and Roth employee elective contributions are subject to the same aggregate employee deferral limit.
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